圖片.png

    1. public static void main(String[] args) {
    3.             int [][] nums=new int[][]{{ 1,2,3}, { 4,5,6}, {7,8,9}};
    4.             ArrayList<Integer> results = (ArrayList<Integer>) spiralOrder(nums);
    5.             System.out.println("输入为："+Arrays.deepToString(nums));
    6.             System.out.print("输出为:"); System.out.println(results);  
    7.         }
    9.         public static List<Integer> spiralOrder(int[][] numlist) {
    10.             List<Integer> list = new ArrayList<>();
    11.             if (numlist == null || numlist.length == 0 || numlist[0].length == 0)
    12.                 return list;
    13.             int rowMin = 0, rowMax = numlist.length - 1, colMin = 0, colMax = numlist[0].length - 1;
    14.             //顺时针：从左到右，从上到下，从右到左，从下到上
    15.             while (rowMin <= rowMax && colMin <= colMax) {
    16.                 /*遍历第一行，行不动，列加1
    17.                  * 遍历结果1->2->3
    18.                  */
    19.                 for (int i = colMin; i <= colMax; i++)
    20.                     list.add(numlist[rowMin][i]);
    21.                 rowMin++;
    22.                 /*遍历最后一列colMax，列不动，行加1
    23.                  * 遍历结果3->6->9
    24.                  */
    25.                 for (int i = rowMin; i <= rowMax; i++)
    26.                     list.add(numlist[i][colMax]);
    27.                 colMax--;
    28.                 if (rowMin > rowMax || colMin > colMax)
    29.                     break;
    30.                 /*遍历最后一行rowMax，行不动，列减1
    31.                  * 遍历结果9->8->7
    32.                  */
    33.                 for (int i = colMax; i >= colMin; i--)
    34.                     list.add(numlist[rowMax][i]);
    35.                 rowMax--;
    36.                 /*遍历第一列colMin，列不动，行减1
    37.                  * ......
    38.                  */
    39.                 for (int i = rowMax; i >= rowMin; i--)
    40.                     list.add(numlist[i][colMin]);
    41.                 colMin++;
    42.             }
    43.             return list;
    44.         }